> Device Boot Start End Blocks Id System
> /dev/sda1 * 63 163837951 81918944+ 7 HPFS/NTFS/exFAT
> /dev/sda2 163837952 1748725759 792443904 7 HPFS/NTFS/exFAT
> /dev/sda3 1748727806 1953523711 102397953 5 Extended
> /dev/sda4 1947514880 1953523711 3004416 82 Linux swap / Solaris
> /dev/sda5 1748727808 1947514879 99393536 83 Linux
I think I see your problem. /dev/sda3 is your extended table. It is not an actual partition per se, but lists the space occupied by all (subsequent) extended partitions.
However, its type seems wrong: Extended (5). Mine is W95 Ext'd (LBA) (f). That's why Ubuntu doesn't recognize your partitions, and fdisk reports overlapping ones.
It's easy to correct the type from within fdisk:
However, before you do it, it is a dangerous operation, you better wait for oldFred, to see what he says about it.
sudo fdisk /dev/sda
m // List menu of available ops
t // Change partition's system id
It won't touch your NTFS partitions, only your Linux ones, which you don't care anyway. Also you waste space between your partitions.
Once you fix your problem, you may want to go back and tighten them up a bit.